Speaker
Description
Lunar regolith is an important resource for in-situ fabrication and repair (ISFR) in future long-term crewed lunar exploration missions. Its application as a feedstock in additive manufacturing (AM) makes possible the rapid, on-demand production of ceramic spare parts and structural components for lunar outposts. However, the brittle nature of regolith-based ceramics limits its scope of possible applications for ISFR operations.
The range of possible applications can be significantly expanded through hybrid manufacturing and rapid metal casting. Casting in 3D-printed ceramic molds can help produce precise metal parts with intricate geometries, which may help meet the demand for spare parts and instruments needed for the maintenance or expansion of future lunar outpost facilities. In the future, it may help ensure the redundancy and sustainability of lunar outposts. Such molds can be 3D-printed via vat-polymerization-based AM using beneficiated regolith feedstock, while the metal needed for casting may be sourced by recycling scrap parts, such as used landing hardware. In the present study, we have shown that such molds can be effectively utilized for aluminum casting. It was demonstrated that DLP-printed regolith ceramic molds effectively withstand thermal shock during casting and exhibit optimal wetting with aluminum melt without sticking, paving the way for the fabrication of reusable molds. We were able to cast both simple geometries and complex parts (gears, wrench keys, bolts), achieving good surface finish and low porosity (<1%) while preserving fine structural details. The microstructure of cast 6061 and A356 aluminum parts was studied using optical microscopy and SEM coupled with EDX. Their mechanical performance was evaluated through tensile, bending, and microhardness tests. The produced aluminum parts exhibited a homogeneous microstructure and high mechanical performance. Results were compared with the state-of-the-art in aluminum rapid casting. Overall, we have demonstrated the high potential of manufacturing complex and precise casting molds using vat-polymerization-based additive manufacturing of lunar regolith ceramic molds, paving the way for advanced aluminum casting capabilities on the Moon.